The invention is particularly well suited for use in the inspection of wire reinforced tires by X-raying them, for example, in accordance with any of the systems or apparatuses described in U.S. Pat. Nos. 3,621,246; 3,621,247; 3,761,722, and 3,789,226. Such systems essentially comprise rotating a tire, to be inspected, about its center axis. An X-ray tube is positioned for emitting X-rays through the rotating tire from the inner peripheral surface thereof. The X-rays are received on an input screen of an image amplifier tube which is positioned outside the tire in alignment with the port through which the rays emit from the X-ray tube. A television camera, affiliated with the output screen of the image amplifier tube, is used to communicate visual information of the internal construction of the tire to a television monitor which is located in a room remote from where the tire is being X-rayed. The density of the televised achromatic images of the internal construction of the tire appearing on the TV monitor, can be varied by conventional adjustments for lightening and darkening the images or pictures. Moreover, the images can be enlarged on the TV monitor to view smaller details of the tire construction, if necessary.
The system of inspecting tires by X-raying them has proven beneficial in locating defects not readily discernible by other methods. However, it is difficult pin-pointing the actual location of a defect when it is observed on the TV monitor. The invention is directed to a mechanical indicator for visually showing an operator, watching the TV monitor, just where the defect is on the tire. The invention is especially useful in checking tires to determine if they are built according to specification. The specification to which a tire is built indicates the arcuate positions where the different splices of the various components should be made around the tire. The tire is conveniently sectionalized like a clock so that a particular splice can be specified as being, for example, at the 12, 2, or 6 o'clock position. A tire builder's number is normally molded in the outer sidewall of the tire adjacent the tread splice which is considered to be at the 12 o'clock position. It can be appreciated that using the system of X-raying a tire, the various locations of the different splices can be easily checked on the television monitor, if the various sectors of the clock are also readily discernible. The invention accomplishes this.
Briefly stated, the invention is in a device for identifying the location of a defect in a tire being X-rayed. The device comprises a continuous band which is positioned around the tire. The band has a thickness and density for producing on a television monitor, an achromatic image which does not interfere with the observance of images of important components of the tire desired to be inspected. A predetermined set of indicia, such as Arabic numerals, are spaced equally around the band. The numerals each have a thickness and density for producing on the television monitor, an achromatic image which visually contrasts with the corresponding images produced by the components of the tire desired to be viewed, such that the indicia are readily discernible on the TV monitor. Thus, any defect discovered in the tire can be quickly related to indicia also visible on the TV monitor.